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Re:Tell HN: Tesla rear-ended me on autopilot, no one will in... by raylad on Monday November 01, 2021 @05:52PM (#29073676)
This does sound like something that should be the subject of a recall investigation.
Re:Tell HN: Tesla rear-ended me on autopilot, no one will in... by tshaddox on Monday November 01, 2021 @06:30PM (#29074104)
Genuine question, what temperature are cars expected to be stored at safely? I'm not talking about engine temperature, just literally the room temperate of the garage. I'm not wanting to excuse or accuse anyone here, but are cars supposed to be manufactured such that they can sit in 150F garages for days at a time without any maintenance?
Re:Tell HN: Tesla rear-ended me on autopilot, no one will in... by leoedin on Tuesday November 02, 2021 @06:30AM (#29079273)
Because cars sit out in the sun in hot countries all day (unavoidably), the automotive supply chain have developed quite rigorous standards for pretty much everything in a car.

Typically every electronic component must be rated from -40 to +105 C. I'd imagine there's similar requirements for all the interior parts of a car too. Cars have a lot of glass, so get very hot in direct sunlight and quickly reach ambient on cold nights.

The reason cars take so long to "catch up" to consumer electronics (eg it's only in the last year or two that large LCD displays have started appearing in cars, or that LED headlights have become commonplace) is that the car design cycle is very long - typically about 7 years. Tesla decided to do things differently, which meant they could iterate much quicker. It also meant they used components not qualified for automotive use. Mostly they got away with it, but there have been some issues (for example their large displays started failing in hot countries).

Re:Tell HN: Tesla rear-ended me on autopilot, no one will in... by heavyset_go on Monday November 01, 2021 @07:09PM (#29074486)
There are a lot of cars that get parked in the hot Arizona sun everyday, where temperatures outdoors can exceed 100 F and interior temperatures can exceed 150 F[1].

[1] https://www.desertsun.com/story/life/home-garden/james-corne...

Re:Tell HN: Tesla rear-ended me on autopilot, no one will in... by kymaz on Monday November 01, 2021 @11:15PM (#29076529)
I would expect SOME vehicles to do so just fine.

Really hot weather in the Continental USA can be pretty toasty, and if a garage was designed more like a crummy solar furnace, I would expect to see it hit those temperatures.

My car has survived at least 150F interior temperatures parked outside during a sunny Pacific Northwest heatwave. I'm estimating that temp because I had some plastic in the car that was rated to lose stiffness at 150F and it got a bit floppy after the car was parked outside in sunny 105F+ weather weeks on end and the plastic was in shade.

It can be hard on lead acid batteries and shorten their life, some lithium ion battery chemistries top out at 130F ambient operating temperature, and ABS plastic that dashboards can be made of is rated to about 176F. If its 150F ambient, the dash could be even hotter.

Re:Tell HN: Tesla rear-ended me on autopilot, no one will in... by jmpman on Tuesday November 02, 2021 @10:45AM (#29082039)
When the Tesla technician came out to replace the camera anti reflection shield, the plastic just crumbled in his hands.

Btw, they never actually replaced the camera, just the anti reflection shield, and cleaned the windshield and the camera lens.

Re:Tell HN: Tesla rear-ended me on autopilot, no one will in... by ihattendorf on Monday November 01, 2021 @07:17PM (#29074586)
> my car is parked outside ... the interior temperatures can easily rise over 150f

I live in Arizona as well and this is why you'll see everyone in parking lots parking under trees in the summer, with empty spaces in between.

Teslas have overheat protection (turns on the AC when interior temp > 105F) for a reason (one of them because it's cheaper to manufacture cars that don't need to withstand higher temperatures).

Re:Tell HN: Tesla rear-ended me on autopilot, no one will in... by xwdv on Monday November 01, 2021 @06:34PM (#29074151)
Your garage is not 150F, and certainly not for days at a time.
Re:Tell HN: Tesla rear-ended me on autopilot, no one will in... by jmpman on Tuesday November 02, 2021 @10:43AM (#29082004)
It’s not parked in a garage. Outside, facing southwest, in the Phoenix summer.

Tesla’s overheat protection only works for 12 hours at a time. If I were commuting, then maybe this wouldn’t have happened, but during Covid, the car was just sitting there for days without being driven. Tesla doesn’t offer a way to extend overheat protection past 12 hours, even when plugged in.

Re:Tell HN: Tesla rear-ended me on autopilot, no one will in... by tshaddox on Monday November 01, 2021 @06:46PM (#29074258)
Indeed mine certainly is not, but apparently the parent commenter's routinely reaches 150F.
Re:Tell HN: Tesla rear-ended me on autopilot, no one will in... by hoppyhoppy2 on Monday November 01, 2021 @08:27PM (#29075282)
I assumed they were referring to the interior of the vehicle rather than the interior of a building.
Re:Tell HN: Tesla rear-ended me on autopilot, no one will in... by kfprt on Monday November 01, 2021 @07:13PM (#29074541)
I suppose teslas could come with warnings, "this vehicle is not intended for use in Arizona".
Re:Tell HN: Tesla rear-ended me on autopilot, no one will in... by MomoXenosaga on Monday November 01, 2021 @06:03PM (#29073797)
I wonder if the US government is afraid to kill their golden goose like what happened with Boeing.

EV is the future and China is moving fast.

Re:Tell HN: Tesla rear-ended me on autopilot, no one will in... by stfp on Monday November 01, 2021 @06:05PM (#29073822)
EV != Tesla and Tesla != Autopilot Also maybe hydrogen is the future?
Re:Tell HN: Tesla rear-ended me on autopilot, no one will in... by outworlder on Monday November 01, 2021 @06:18PM (#29073959)
> Also maybe hydrogen is the future

It definitely isn't if we are going to move away from fossil fuels.

Re:Tell HN: Tesla rear-ended me on autopilot, no one will in... by gumby on Monday November 01, 2021 @06:39PM (#29074197)
You can get H+ by cracking water. You “just” need a source of cheap energy.

Storage is tough — those protons are really tiny and it’s hard to keep them from escaping

Re:Tell HN: Tesla rear-ended me on autopilot, no one will in... by outworlder on Monday November 01, 2021 @07:01PM (#29074413)
> You can get H+ by cracking water. You “just” need a source of cheap energy.

Well aware. But we don't have a source of cheap energy. And guess what, whatever source of energy we have, it is very wasteful to produce hydrogen.

First, you need electrolysis. Around 80% efficient. However, in order to get any usable amount of energy per volume out of it, you need to either compress hydrogen (using more power) or liquefy it (way more power, boiloff problems).

Now you need to transport it, physically. This uses more power, usually with some big trucks driving around, just as we have today with gasoline and diesel.

This will get stored into some gas station equivalent. All the while losing mass, as those protons are hard to store, indeed.

Now you can drive your vehicle and refill. Some inefficiencies here too but we can ignore them unless you need to travel long distances to refuel.

This hydrogen will generally be used in a fuel cell. The output of the fuel cell is... electrical energy (+water)

You could skip all that, use the electricity from the power grid to directly charge batteries. No hydrogen production plants needed, no container challenges, no diffusing through containers and embrittlement to worry about. No trucks full of hydrogen going around. Electricity is found almost everywhere, even in places where there's little gas infrastructure.

Mind you, hydrogen has another disadvantage, other than thermodynamics: it ensures control is kept with the existing energy companies. We would still need to rely on their infrastructure to refill our cars (much like gas stations). They would like to keep it that way. Ultimately it doesn't really matter what's the fuel we are using, as long as we keep driving to gas stations.

Re:Tell HN: Tesla rear-ended me on autopilot, no one will in... by HWR_14 on Tuesday November 02, 2021 @10:31AM (#29081827)
If hydrogen fuel cells lasted longer than batteries (in lifespans, not-per charge) or required fewer rare metals to create, I can see a giant win. EVs are pretty wasteful if you consider the entire car lifespan and not just what the end consumer fills up with, to the point that I feel the ecologically superior action is just to drive an old ICE.
Re:Tell HN: Tesla rear-ended me on autopilot, no one will in... by outworlder on Tuesday November 02, 2021 @02:44PM (#29085685)
> required fewer rare metals to create

Fuel cells require expensive and exotic catalysts, like platinum. So they don't even win there.

Hydrogen might have aviation uses but I'm just as skeptical we'll get over the safety issues.

> EVs are pretty wasteful if you consider the entire car lifespan

Only until the required recycling infrastructure is in place. We can recycle around 96% of the material used in batteries. There's much less equipment needed for an EV, compared to ICE. There's also a push to use less of rare earth minerals like cobalt. Any advances in battery tech (like solid state batteries) can be easily incorporated, as electric motors don't care where the electricity comes from.

EVs don't have spark plugs(consumable), oil pumps and filters, alternators(the drive motors work as alternators for regen braking), air filters, crankshafts, valves, pistons, exhaust(and catalytic converters with rare metals), starter motor... the list goes on. Even the brake pads last longer. It's at a minimum a battery bank, an electric motor, and some electronics to manage power. An order of magnitude less moving parts (that have to be manufactured, wear out, and have to be replaced).

> the ecologically superior action is just to drive an old ICE.

An old but relatively recent, fuel-injected ICE with the latest emissions standards? Probably much than getting a new one built, yes.

A really old one with a busted engine (or one before we had catalytic converters in the exhaust)? Then I do not know. Might be better to scrap and get a somewhat less old vehicle.

Honestly, the ecological win here would be to convert the existing fleet into EVs, rather than creating entirely new cars. There are some hobbyists doing that successfully. It's not even difficult - the difficult part is adapting the parts to fit the specific vehicle. The economics may be difficult to justify, however.

At some point, when we have a sizable EV fleet, getting recycled batteries into them would be the way to go. They will probably last longer than our current ICE vehicles.

Re:Tell HN: Tesla rear-ended me on autopilot, no one will in... by catlikesshrimp on Tuesday November 02, 2021 @11:59PM (#29090968)
You speak as if lead-acid batteries, the most recycle-friendly battery, had anything in common with EV batteries, besides being batteries.

If a lead acid battery is bread in a bag, a Lithium battery is a tacobell combo: much more energy, much more waste material.

Reduce comes before Reduce and Recycle

Re:Tell HN: Tesla rear-ended me on autopilot, no one will in... by gumby on Monday November 01, 2021 @11:18PM (#29076549)
I agree, H+ is a dumb approach.
Re:Tell HN: Tesla rear-ended me on autopilot, no one will in... by BenjiWiebe on Tuesday November 02, 2021 @12:30AM (#29077108)
And H2 isn't much better.
Re:Tell HN: Tesla rear-ended me on autopilot, no one will in... by catlikesshrimp on Tuesday November 02, 2021 @11:54PM (#29090950)
Hydrogen as fuel is unrelated to fossil fuels. Look it up. Edit: 95% of hydrogen is currently produced from hydrocarbons. BUT Electrolysis

https://en.m.wikipedia.org/wiki/Electrolysis_of_water Hydrogen as a fuel has been tested in buses. Works a proof of concept.

This was about hyundai marketing hydrogen as a fuel:

https://www.economist.com/science-and-technology/2020/07/04/...

In the end, it will depend on the energy conversion efficiency that can achieved in the future.

Re:Tell HN: Tesla rear-ended me on autopilot, no one will in... by nameisname on Monday November 01, 2021 @06:35PM (#29074161)
Can't renewables produce hydrogen?
Re:Tell HN: Tesla rear-ended me on autopilot, no one will in... by outworlder on Monday November 01, 2021 @06:49PM (#29074279)
They can. But overwhelmingly, they do not. It's much cheaper to extract hydrogen from fossil fuels and that's not likely to change any time soon.
Re:Tell HN: Tesla rear-ended me on autopilot, no one will in... by ipsum2 on Monday November 01, 2021 @06:05PM (#29073823)
All major car companies manufacture EVs. Off the top of my head, I've seen BMW, Prius (Toyota), Honda electric cars outside recently.
Re:Tell HN: Tesla rear-ended me on autopilot, no one will in... by catlikesshrimp on Wednesday November 03, 2021 @12:01AM (#29090984)
Hydrogen production should be coupled to renewable energy production in the way they will pair bitcoin mining to any energy plant